PRODUCTION OF CARRIER-FREE Na-24 BY IRRADIATION OF PURE Mg MATRICES IN POOL-REACTORS

摘要

Carrier-free Na24 can be produced by irradiating high-purity Mg matrices in the fast-neutron fluxes of pool-reactors :13 to 26 mC Na24 per gram Mg can be obtained for 4-day irradiations in the RSI reactor.nA radiochemical method based on the electrodeposition of the Na24 activity on a Hg cathod was developed :0.5-g amounts of Mg can be processed in 4 hours, with nearly quantitative recoveries (93 ± 5 ％) and high decontamin¬ation factors from the matrix (1.5 to 5 x 103). The procedure is described and the results of some production experiments at mC level are reported. The specific activity obtained when using 09.99 ％ Mg was found to be in the order of 90 C/g, and the radiochemical purity about 99.9％, for 4-day irradiations at 2 x 1013 fast neutron/cm2 sec, taking into account a 15-hour decay (treatment and delivery time).